width YAMAHA YZ85 2005 Owners Manual

SPEC
2 - 1
GENERAL SPECIFICATIONS
EC200000
SPECIFICATIONS
EC211000
GENERAL SPECIFICATIONS
Model name: YZ85 YZ85LW
YZ85T (USA, CDN,
AUS, NZ)
YZ85 (EUROPE, ZA)YZ85LW (EUROPE)
YZ85LWT (AUS, NZ)
Model code number: YZ85 YZ85LW
5PAA
(USA, CDN, EUROPE,
ZA)
5PAB
(AUS, NZ)5SHA
(EUROPE)
5SHB
(AUS, NZ)
Dimensions: YZ85 YZ85LW
Overall length 1,821 mm (71.7 in) 1,903 mm (74.9 in)
(USA, ZA)
1,818 mm (71.6 in)
(EUROPE, CDN, AUS,
NZ)
Overall width 758 mm (28.9 in)←
Overall height 1,161 mm (45.7 in) 1,205 mm (47.4 in)
Seat height 864 mm (34.0 in) 904 mm (35.6 in)
Wheelbase 1,258 mm (49.5 in) 1,286 mm (50.6 in)
(USA, ZA)
1,255 mm (49.4 in)
(EUROPE, CDN, AUS,
NZ)
Minimum ground clearance 351 mm (13.8 in) 393 mm (15.5 in)
Dry weight: YZ85 YZ85LW
Without oil and fuel 66 kg (145.5 lb) 69 kg (152.1 lb)
Engine:
Engine type Liquid cooled 2-stroke, gasoline
Cylinder arrangement Single cylinder, forward inclined
Displacement 84.7 cm
3 (2.98 Imp oz, 2.86 US oz)
Bore × stroke 47.5 × 47.8 mm (1.870 × 1.882 in)
Compression ratio 8.2 : 1
Starting system Kickstarter
Lubrication system: Premix (30 : 1) (Yamalube 2-R)
Oil type or grade (2-cycle):
Transmission oil Yamalube 4 (10W-30) or SAE 10W-30 type SE
motor oil
Periodic oil change 0.50 L (0.44 Imp qt, 0.52 US qt)
Total amount 0.55 L (0.48 Imp qt, 0.58 US qt)
Coolant capacity (including all routes): 0.54 L (0.48 Imp qt, 0.57 US qt)
Air filter: Wet type element
2

SPEC
2 - 5
MAINTENANCE SPECIFICATIONS
Crankshaft:
Crank width “A”44.90 ~ 44.95 mm
(1.768 ~ 1.770 in)----
Runout limit “C”0.03 mm (0.0012 in) 0.08 mm
(0.003 in)
Big end side clearance “D”0.20 ~ 0.70 mm
(0.008 ~ 0.028 in)----
Small end free play “F”0.5 ~ 1.2 mm
(0.020 ~ 0.047 in)2.0 mm
(0.08 in)
Clutch:
Friction plate thickness 2.9 ~ 3.1 mm
(0.114 ~ 0.122 in)2.7 mm
(0.106 in)
Quantity 7 ----
Clutch plate thickness 1.8 ~ 2.2 mm (0.071 ~ 0.087 in) ----
Quantity 6 ----
Warp limit ---- 0.1 mm
(0.004 in)
Clutch spring free length 33.0 mm (1.30 in) 31.0 mm
(1.22 in)
Quantity 5 ----
Clutch housing thrust clearance 0.10 ~ 0.35 mm
(0.0039 ~ 0.0138 in)----
Clutch housing radial clearance 0.022 ~ 0.051 mm
(0.0009 ~ 0.0020 in)----
Clutch release method Inner push, cam push ----
Shifter:
Shifter type Cam drum and guide bar ----
Guide bar bending limit ---- 0.05 mm
(0.002 in)
Kickstarter:
Type Kick and mesh type ----
Carburetor:
Type/manufacturer PWK28/ KEIHIN ----
I. D. mark 5PA1 00 ----
Main jet (M.J) #138 ----
Jet needle-clip position (J.N) NBKF-2 ----
Main nozzle (N.J)ø3.4 ----
Cutaway (C.A) 3.0 ----
Pilot jet (P.J) #45 ----
Pilot air screw (example) (P.A.S) 2 ----
Starter jet (G.S) #62 ----
Float height (F.H) 18 ~ 20 mm (0.71 ~ 0.79 in) ----Item Standard Limit

SPEC
2 - 6
MAINTENANCE SPECIFICATIONS
Reed valve:
Thickness “T”0.42 mm (0.017 in) ----
Valve stopper height 7.4 ~ 7.8 mm (0.291 ~ 0.307 in) ----
Valve bending limit ---- 0.2 mm
(0.008 in)
Cooling:
Radiator core size
Width 117.8 mm (4.64 in) ----
Height 240 mm (9.45 in) ----
Thickness 32 mm (1.26 in) ----
Radiator cap opening pressure 95 ~ 125 kPa (0.95 ~ 1.25 kg/cm
2,
13.5 ~ 17.8 psi)----
Radiator capacity 0.32 L (0.28 Imp qt, 0.34 US qt) ----
Water pump
Type Single-suction centrifugal pump ----Item Standard Limit

4 - 42
ENG
REMOVAL POINTS
Impeller shaft
1. Remove:

Impeller 1

Washer 2

Impeller shaft 3
NOTE:
Hold the impeller shaft on its width across the
flats a with spanners, etc. and remove the
impeller.
5PA41250
EC4G3210
Oil seal
NOTE:

It is not necessary to disassemble the water
pump, unless there is an abnormality such
as excessive change in coolant level, discol-
oration of coolant, or milky transmission oil.

Replace the oil seal whenever it is remov-
aled.
1. Remove:

Bearing 1
2. Remove:

Oil seal 1
5PA41260
5PA41270
INSPECTION
EC444200
Impeller shaft
1. Inspect:

Impeller shaft 1
Bend/wear/damage → Replace.
Fur deposits → Clean.
5PA41280
WATER PUMP

4 - 44
ENG
2. Install:

Bearing 1
NOTE:
Install the bearing by pressing its outer race
parallel.
5PA41330
Impeller shaft
1. Install:

Impeller shaft 1

Washer 2

Impeller 3
NOTE:

Take care so that the oil seal lip is not dam-
aged or the spring does not slip off its posi-
tion.

When installing the impeller shaft, apply the
lithium soap base grease on the oil seal lip
and impeller shaft. And install the shaft while
turning it.

Hold the impeller shaft on its width across
the flats a with spanners, etc. and install the
impeller.
5PA41340
T R..14 Nm (1.4 m · kg, 10 ft · lb)
5PA41350
2. Install:

Gasket (water pump housing) 1
5PA41360
3. Install:

Water pump housing 1

Bolt (water pump housing) 2

Copper washer (coolant drain bolt)
3

Coolant drain bolt 4
5PA41370
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
WATER PUMP

4 - 56
ENG
Crankshaft
1. Measure:

Runout limit a

Small end free play limit b

Connecting rod big end side clearance c

Crank width d
Out of limit → Replace.
Use the dial gauge and a thickness gauge.
Dial gauge and stand:
YU-3097/90890-01252
Standard
Runout
limit:0.03 mm
(0.0012 in)0.08 mm
(0.003 in)
Small end
free play:0.5 ~ 1.2 mm
(0.020 ~ 0.047 in)2.0 mm
(0.08 in)
Side
clearance:0.20 ~ 0.70 mm
(0.008 ~ 0.028 in)—
Crack
width:44.90 ~ 44.95 mm
(1.768 ~ 1.770 in)—
5PA41680
5PA41690
EC4N5000
ASSEMBLY AND INSTALLATION
Crankshaft bearing
1. Install:

Bearing 1
To left and right crankcase.
NOTE:
Install the bearing by pressing its outer race
parallel.5PA41700
Oil seal
1. Install:

Oil seal 1
NOTE:

Apply the lithium soap base grease on the oil
seal lip.

Install the oil seal with its manufacture’s
marks or numbers facing outward as shown.
5PA41710
CRANKCASE AND CRANKSHAFT